In the art of door design, it has become architecturally fashionable to use large expanses of glass, for aesthetic reasons. In doing so, the tendency has been to minimize the use of obtrusive supporting structures, to permit maximum aesthetic presentation of the glass.
Where doors are being utilized across an opening, it has also become desirable to enhance the presentation of the doors by using glass sidelights on the sides of the doors, and, where possible, to use a pair of openable doors. Where ceiling height permits, it has also become fashionable to utilize a glass transom above the doors.
In such constructions, particularly where two sidelights are utilized along with a transom, and with a double door arrangement, each sidelight is secured to the building structure at the ceiling, floor, and along one wall. Such can be done by embedding the sidelight into the building structure at those locations, so as to minimize the presentation of glass fixtures. When the glass is embedded in the building structure, generally fixtures will be utilized, but they will preferably be embedded to as to give a clear, unbroken presentation of the glass.
Similarly, in the past, the glass transom has been embedded into the building structure at its upper end, along with a suitable fixture for carrying the same, and the glass hangs downwardly to a position just above the upper ends of the door or doors. Generally, also, the transom will be notched out at its lower end, at those locations at which it is necessary to accommodate one or more bearings for door pivot pins, in order to permit the doors to move between open and closed positions. Usually, also, the transom and sidelights are provided with fixtures in the notched-out portions of the transom, for tying the side light to the transom at each end of the transom, for facilitating mutual support between the transom and sidelight at each such location, in directions at right angles to the planes of the glass, and also to provide support for the upper pivot bearing for an associated door, likewise in directions at right angles to the glass. Also, bearings for doors are mounted in the notched-out portions of the transom.
In such constructions heretofore employed, the transom is essentially hanging from the ceiling, and after the passage of time, with or without minor building movement as for example due to settlement, stresses can become induced in the glass that may render the glass prone to breakage, if, as for example, the door is violently slammed, or if a door or side light is accidentally struck. In such a case, the transom may shatter and fall, causing damage to persons or property.